System for and method of exchanging server data in packet unit

ABSTRACT

A packet switch apparatus including a plurality of connecting points, each being coupled to one of a plurality of data processing units, and apparatus for receiving a first packet including identification information of a first data processing unit via a first connecting point. The invention further includes a storage for storing correspondence between the first data processing unit and the first connecting point based on the identification information. Apparatus, responsive to reception of a second packet from a second data processing unit to be transmitted to the first data processing unit, transmits the second packet to the first data processing unit via the first connecting point based on the correspondence stored in the storage.

The present application is a continuation of application Ser. No.10/424,717, filed Apr. 29, 2003; which is a continuation of applicationSer. No. 09/161,731, filed Sep. 29, 1998, now U.S. Pat. No. 6,621,816;which is a continuation of application Ser. No. 08/653,276, filed May24, 1996, now U.S. Pat. No. 6,141,338; which is a continuation ofapplication Ser. No. 07/798,965, filed Nov. 27, 1991, now U.S. Pat. No.5,537,401, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a server system of a type wherein thesharing of resources can be carried out using extensions of a privatebranch exchange (PBX), and more specifically to a system for and amethod of exchanging server data in a packet unit, of a type wherein aplurality of users can simultaneously utilize the same resource.

As one of conventional arts, there is known one disclosed in JapanesePatent Application Laid-Open No. 1-109847. According to the disclosure,peripheral devices such as a printer, hard disc are electricallyconnected to an exchange network of a digital exchanger through a datainterface unit. On the other hand, a data Processing unit iselectrically connected to the exchange network of the digital exchangerthrough a data access unit. In the conventional art having such anarrangement, terminals are electrically connected to the data Processingunit and the peripheral devices (servers) by making use of exchangefunctions of the digital exchanger. The digital exchanger is providedwith connecting shared buses for the purpose of control of theperipheral devices. The buses are interconnected to internal buses of adata processing control device. When a plurality of peripheral devicesare connected to the exchange network, the data processing controldevice can accept operation requests of other peripheral devices whileone peripheral device is in operation. Thus, the data processing controldevice connects a line for a peripheral device to which a use requesthas been made to a line for a corresponding peripheral device. Accordingto the prior art, as described above, a plurality of peripheral, devicescan simultaneously be utilized by connecting the peripheral devices toseparate lines.

The above disclosure does not take into consideration a case where userequests are made to the same peripheral device from a plurality ofterminals (lines). When one terminal makes use of the peripheral device,other terminals cannot use it, with the result that they had to wait forits use until a process of the terminal while being using the peripheraldevice is completed.

In the above prior art, the data processing unit needs dedicated controlbuses in order to control the peripheral devices. It is necessary toplace connection terminals used to connect the peripheral devices to theexchange network and extending from the data interface unit, and thecontrol buses in all Possible places where the peripheral devices can bedisposed. In order to ensure that users can freely travel over theperipheral devices, it is thus necessary to provide data interface unitsin the digital exchanger by the number of possible places where theperipheral devices can be placed it is also necessary to placeconnection terminals extending from data interface units and controlbuses in all possible locations where the peripheral devices can bedisposed. Thus, there was need for the provision of excessive equipment.

The above prior art does not give consideration as to the fact that auser travels over the peripheral devices so as to be connected toanother line. Thus, when the user travels over the peripheral devices soas to change a connection line, a table indicative of the correspondingrelation between numbers of the connection terminals for the connectionof the peripheral devices, which numbers being held by the digitalexchanger and practically-connected peripheral devices, was renderednecessary to be rewritten by either a user or a system controller. Itwas also necessary to inform all the users who make use of theperipheral devices of a connection line number change message.

In addition, the above prior art does not give consideration as to thesecurity against information stored in disc devices. When a messagerelative to a line number to which a peripheral device is connected isreceived, a response to a connection request was made without reserve.

OBJECT OF THE INVENTION

It is therefore a first object of the present invention to provide asystem for exchanging server data in a packet unit, of a type wherein aplurality of terminals can simultaneously utilize the same peripheraldevice (server).

It is a second object of the present invention to provide a system forexchanging server data in a packet unit, of a type wherein physicalinterfaces identical to telephones can provide the electricalconnections between terminals and servers.

It is a third object of the present invention to provide a system forexchanging server data in a packet unit, of a type wherein serversconnected to users who are using terminals and to a network canautomatically be registered and/or deleted, thereby making it possibleto freely change locations where the servers are placed and to cause theusers to freely travel over the terminals.

It is a fourth object of the present invention to provide a system forexchanging server data in a packet unit, of a type wherein only usersallowed to use servers can utilize the servers, and users capable ofreading and writing data therefrom and therein can be assigned accordingto the degree of secrecy of information held by the servers.

SUMMARY OF THE INVENTION

A description will now be made of a summary of operations of the presentinvention, which range from the completion of the entry of users interminals connected to a network to the time that the users can utilizeservers. When a user entry is confirmed, a piece of terminal equipmentacquires a user ID and a user's password. Thereafter, the terminalequipment is activated to carry out a process for setting up orestablishing a packet link between the terminal equipment and a packetcontrol on a PBX side. When the packet link is set up therebetween, theterminal equipment sends a server use request packet for thetransmission of the user ID and the user's password to the packetcontrol.

The packet control receives the server use request packet from theterminal equipment, and makes a check as to which terminal equipment hastransmitted the user ID and the user password to the packet control.Thereafter, the packet control stores a physical address of the checkedterminal equipment therein. Then, the packet control sends the user IDand the password to a terminal control.

The terminal control checks whether or not the user of the received userID has been entered. A user name, a user ID, a user's password, and auser's information access level to all of which entry permission hasbeen given, a server ID of each server connectable to a system, and theclassification and attribute of each server, have been stored in theterminal control by a system controller. Then, such information isregistered on a second table, and is deleted only when the systemcontroller carries out information delete operation. The terminalcontrol retrieves a user ID entry information from the informationstored in the second table. If it is judged that the received user IDhas already been registered on the second table, then the registeredpassword is collated with the user's password. If it is judged to be anavailable user, then a check is made as to whether or not an availableserver is present by reference to the information access class of theuser. Thereafter, information about a server name and a server attributeis sent to the packet control. If it is judged to be an unavailableuser, an unavailable message is delivered to the packet control.

The packet control receives from terminal control an inquiry as towhether or not the user can utilize the system. If it is judged that theuser can utilize it, then an available server ID and a logical channelnumber (LCN) of a specific logical channel, which corresponds to theserver ID, are retrieved from a first table. Then, a server use responsepacket for the transmission of the retrieved information is sent to thecorresponding terminal equipment. If it is judged that the user cannotutilize the system on the other hand, then an unavailable message istransmitted to the terminal equipment. Thus, the system can be preventedfrom being utilized by a user who has not been registered. When theterminal equipment receives a system available message from the PBX, itstores therein a received server ID and a logical channel number of aspecific logical channel, which corresponds to the server ID.Thereafter, the terminal equipment sends request/data to a server in theform of a data packet added with a specific logical channelcorresponding to the server that the user wants to use.

When the packet control detects that the server has been connected to anetwork and has been brought into a state in which it being capable ofproviding functions as the server, the packet control initiates aprocess for setting up a packet link between the server and the packetcontrol. If the packet link is established, then the server sends apacket for the transmission of data such as a server ID, classificationand attribute of the server to the packet control. Then, the packetcontrol makes a judgment as to which server has transmitted the data.Thereafter, the packet control temporarily stores therein a physicaladdress of a corresponding server, and sends the data to the terminalcontrol.

Then, the terminal control determines whether or not the server of thereceived server ID has been registered. More specifically, the terminalcontrol retrieves a second table on which a user ID, a user password, aserver ID, classification of a server, etc. have been registered by asystem controller. If it is judged that a received server ID has beenregistered on the second table, then the registered classification andattribute of the server are collated with the classification andattribute of the server, which correspond to the received server ID. Ifit is determined that the server has coincided with the registeredserver, then a “connectable message” is sent to the packet control. Ifit is determined to be negative, then an “unconnectable message” isdelivered to the packet control.

The packet control receives from the terminal control an inquiry as towhether or not a server can be connected to the system. If it is judgedthat the server can be connected to the system, then the packet controlserves to register or enter physical address information of the serverand a server ID all of which have temporarily been stored, in a firsttable. Then, the packet control informs the server of a “connectioncomplete message”. If it is judged to be negative, then the packetcontrol sends an “unconnectable message” to the server. Thereafter, adata link between the server and the packet control is released. Thus,the packet control is activated to prevent the system from beingconnected to a server which has not been registered. Thus, the packetcontrol can transmit user use request data to the server.

A description will now be made of a summary of operations of the presentinvention, which range from the delivery of data to a system by a pieceof terminal equipment in which a user has made an entry to the deliveryof data to a server from the system side.

When the terminal equipment sends a data packet having, as a header, alogical channel number as an identifier corresponding to a specificserver, to a PBX, a packet control carries out a process for enteringdata in means for accepting and registering data to be transmitted to acorresponding server. It is then determined whether or not the previousdata outputted from the user who has transmitted the above data to thesystem has already been entered in the means. If it is determined to benegative, then the data is entered in the rearmost location of a userequest data reception queue. If it is determined to be positive, thenthe packet control examines the data existing in the rearmost location,of the data which have already been entered in the use request datareception queue, and checks whether or not the data has reached the mostsuitable data size to be delivered to the server. If the answer isdetermined to be no, then some or all of the data sent from the user isassembled into the data existing in the rearmost location, of the datafrom the same user, which have already been entered in the use requestdata reception queue. If some of the data sent from the user isassembled into the data referred to above or some or all of the data isnot completely assembled into the data, then the data is divided intothe most suitable data size of a packet to be delivered to the server,after which each divided data is entered in the use request datareception queue. When the server is in a data acceptable state, thepacket control sends to the server a packet for the transmission of dataentered in the head of the use request data reception queue. At thistime, an identifier for the identification of the user is inserted intothe head of the packet to be sent to the server. Thus, the user cantransmit data to an intended server.

A description will now be made of the summary of the operations of thepresent invention at the time that an improper user who has not beenallowed to use the system has made an entry trial in the system. A userfirst makes an entry in the terminal equipment and the terminal controlcarries out an inquiry as to its entry. As a result, it is judged thatthe user has not been allowed to use the system. When the terminalequipment receives a system unavailable message from the PBX, theterminal equipment is activated to set up a counter for counting thenumber of use refusals of the server system, which is notified from thesystem side. In addition, the terminal equipment stores therein a userID used when the entry trial of the user is made, and starts a firsttimer for counting the time from the time at which a server system userefusal or rejection message is received to the time at which a givenperiod has elapsed. When the terminal equipment receives again a serversystem use rejection message from the system before the first timer istimed out, the terminal equipment restarts the first timer, therebyincrementing the counter. When the value counted by the counter exceedsthe number of times N defined in advance at the time of the design ofthe system before the first time is timed out, the terminal equipmentjudges that an improper user is now entering the system. Accordingly,the terminal equipment informs the system of a message indicative of theentry of the improper user in the system, followed by starting of asecond timer for counting the time required to separate the terminalequipment from the system. When the second timer is in operation, theterminal equipment refuses the entry of any user in the system. When animproper user invasion or entry message is received from the terminalequipment, the PBX is activated to inform a system controller of amessage indicative of the fact that the improper user being now enteringthe system. The previously described data to be transmitted between theterminal equipment and the server is transmitted in a code or cryptomode exclusive of data used for the setting up and the release of thedata link. Thus, the improper user cannot easily enter into the systemeven when the improper user who has not been allowed to use the system,attempts to enter into the system.

According to the present invention, as described above, a server systemcan be utilized by making use of -extensions of an exchanger. Therefore,a user can freely travel over each terminal equipment which makes use ofa server. Since both a telephone and the server system can be utilizedthrough the same network, it is unnecessary to doubly lay cables fortheir purposes. By making use of the identical logical channelcorresponding to each server device, a plurality of pieces of terminalequipment can simultaneously set up or establish a packet link andaccept a plurality of use requests to the identical server. Therefore,any user is no longe±− placed on a process waiting state because server'use requests do not compete with each other. When the user attempts touse the server, a server name to be used is assembled into data, andthus-processed data is delivered to the system. In addition, the systemexamines a physical address of the server, followed by delivery of datato the server. It is therefore unnecessary for the user to store anextension number of an extension connected with a server, etc. when theuser makes use of the server. Since the terminal equipment which hascontinuously failed in the system entry through a given number of timesor more, is separated from the system, a system entry trial is rendereddifficult. In addition, an information access level is established foreach user, and a server available for each user is assigned based on theaccess level thus established. Therefore, each server having a varietyof security levels can be connected to the system. Furthermore, serveruse request data received from the user is temporarily registered in aqueue, and such data is shaped into a data size capable of providing themost suitable server's process for each server when it is entered in thequeue, thereby making it possible to efficiently carry out server's dataprocessing.

The above and other objects, features and advantages of the presentinvention will become apparent from the following description and theappended claims, taken in conjunction with the accompanying drawings inwhich preferred embodiments of the present invention are shown by way ofillustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a PBX server system according to a firstembodiment of the present invention;

FIG. 2 is a diagram schematically showing an internal structure of a PBXin the system shown in FIG. 1;

FIG. 3 is a diagram schematically illustrating an internal structure ofterminal equipment in the system shown in FIG. 1;

FIG. 4 is a diagram schematically depicting an internal structure of aserver in the system shown in FIG. 1;

FIG. 5 is a diagram schematically showing an internal structure ofanother example of the terminal equipment shown in FIG. 1;

FIG. 6 is a diagram schematically illustrating an internal structure ofanother example of the server shown in FIG. 1;

FIG. 7 is a diagram showing the structure of the inside of a packetexchange;

FIG. 8 is a diagram for describing an extension table;

FIG. 9 is a diagram for describing a server table;

FIG. 10 is a diagram for describing an entry table used for the PBXserver system;

FIG. 11 is a diagram for describing a logical channel assignment table;

FIG. 12 is a flowchart for describing the sequence of processes carriedout by terminal equipment with an IC card control upon entry of a userin the system;

FIG. 13 is a flowchart for describing the sequence of processesperformed by terminal equipment free of an IC card control upon entry ofa user in the system;

FIG. 14 is a flowchart for describing the sequence of processes carriedout by a communication interface of terminal equipment;

FIG. 15 is a flowchart for describing the sequence of processes made byterminal equipment with an IC card control upon entry of a server in thesystem;

FIG. 16 is a flowchart for describing the sequence of processes carriedout by a server free of an IC card control upon its system entry;

FIG. 17 is a flowchart for describing the sequence of processes carriedout by a packet control upon receipt of a packet for control datacommunication;

FIG. 18 is a flowchart for describing the sequence of user and serverinquiry processes carried out by a terminal control;

FIG. 19 is a flowchart for describing the sequence of server use datadelivery processes performed by a server use control;

FIG. 20 is a flowchart for describing the sequence of processes from thereception of server use data to the entry of data in a server queue,which are carried out by the packet control;

FIG. 21 is a diagram for describing the structure of the server queue;

FIG. 22 is a flowchart for describing the sequence of processes carriedout by the packet control, for delivering data entered in the serverqueue to individual servers;

FIG. 23 is a flowchart for describing the sequence of processes carriedout by the packet control when faults or malfunctions occur in a datalink between a server and a PBX or between terminal equipment and thePBX;

FIG. 24 is a flowchart for describing the sequence of processes forcompletion of the entry of a user in terminal equipment;

FIG. 25 is a flowchart for describing the sequence of processes carriedout by terminal equipment having an IC card control, for completing theentry of a user in the PBX server system;

FIG. 26 is a flowchart for describing the sequence of processes carriedout by the packet control, for utilizing the server system through apublic line;

FIG. 27 is a diagram for describing a public-line table;

FIG. 28 is a flowchart for describing the sequence of processes carriedout by the packet control at the time a user which has used the systemthrough the public line, has finished using the same;

FIG. 29 is a diagram illustrating a PBX server system according to asecond embodiment of the present invention;

FIG. 30 is a diagram schematically showing the structure of the insideof a PBX employed in the system shown in FIG. 29;

FIG. 31 is a diagram for describing an extension table managed by apacket control of the PBX in the system according to the secondembodiment;

FIG. 32 is a diagram for describing a server table managed by the packetcontrol shown in FIG. 31;

FIG. 33 is a diagram showing one example of a packet format employed inthe present invention; and

FIG. 34 is a diagram illustrating one example of a transmission formatemployed when a packet used in the present invention is transmittedusing a control signal channel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will hereinafter bedescribed with the accompanying drawings. FIG. 1 shows a PBX serversystem according to a first embodiment to which a system for exchangingserver data in a packet unit, i.e., a sever data packet exchange systemof the present invention is applied. The PBX server system basicallycomprises a digital public branch exchange (hereinafter referred to as a“PBX”) 100, a plurality of pieces of terminal equipment 101, and aserver 104. The terminal equipment 101 and the server 104 can beconnected to extensions 105 of the PBX through physical interfacesidentical to those of devices such as telephones 102, facsimiles 103,the devices being used for a public telephone communication line. As hasbeen provided in the advice 1.441 (ISDN user/network interface) ofCCITT, each extension 105 of the PBX 100 is used to send a controlsignal transmitted and received between the PBX 100 and each terminalequipment 101 for the purpose of terminal connection and an informationsignal used to make a telephone call and transmit data, through separateor discrete channels. Each extension 105 has at least one control signalchannel and one information signal channel. A plurality of devices canbe connected to one extension 105, and they can simultaneouslycommunicate with one another. The PBX server system is activated totransmit data to the server 104 from the terminal equipment 101 throughthe PBX 100. In addition, the transfer of data between the terminalequipment and the PBX and between the server and the PBX is carried outin the form of a packet unit, using either the control signal channel (Dchannel) or the information signal channel (B channel) in accordancewith the provision of the advice X.25 of CCITT. The exchange of a datapacket delivered to the sever from the terminal equipment is performedin the PBX 100. FIG. 33 shows a packet format provided in the adviceX.25 of CCITT. FIG. 33(a) illustrates a format of a call control packet.The format comprises a general format identifier (GFI), a logicalchannel group number (LCGN), a logical channel number (LCN), a packettype identifier, a packet header including a called terminal address,etc. necessary for the connection of a calling side to a calleddestination or terminal, and user data divided into blocks of givensizes. FIG. 33(b) shows a format of a data packet. The format comprisesa general format identifier (GFI), a logical channel group number(LCGN), a logical channel number (LCN), a packet header includingsequence numbers (P(R), P(S)) of the packet, and user data divided intoblocks of predetermined sizes. In order to distinguish between specialcommunications carried out between the terminal equipment 101 and theextension control 206, a logical channel number is applied to eachpacket in the form of the packet format referred to above. A packetcommunication is carried out for every destinations of respectiveterminal equipment connected to one physical line, so that it can bedistinguished from others by an identifier of data indicative of theso-applied logical channel number. Thus, when a logical channel numbercorresponding to address information is firstly applied to one ofpackets and a packet communication service is initiated, the PBX cansubsequently recognize a desired destination by simply applying thelogical channel number to data. FIG. 34 illustrates a transmissionformat of a user packet based on the D channel provided in the adviceI.441, I.462 of CCITT. In other words, there are provided a serviceaccess point identifier (SAPI) used to manage terminal information foreach physical line and indicate either call control information orpacket information, and a circuit-terminal control indicative of anumber (TEI) is used to identify each multipoint-connected terminal,etc.

FIG. 2 is a diagram schematically showing the structure of the inside ofthe PBX 100. FIG. 2(a) shows the structure of the PBX in which a packetexchange 201 for changing over packet data from the terminal equipmentto the server is directly connected to a time-division multiplex (TDM)path 202 in the PBX 100. Also connected to the TDM path 202 are acentral processing unit (CPU) 203 for controlling the entire operationof the PBX 100, an extension control 205 for controlling the electricalconnections among the extensions 105, and a public line control 206 forcontrolling the electrical connections among public lines 106. A memory204 and control terminal equipment 208 are electrically connected via aCPU bus 207 to the CPU 203, and the memory 204 stores thereininformation about the attribute of each extension and communicationrecords. The control terminal equipment 208 is used to cause a systemcontroller to examine the condition of the PBX in use and to enter theattribute of the extension and change it to another. FIG. 2(b)illustrates the structure of the PBX in which a computer 210 iselectrically connected to a CPU 203 of a PBX 100 through a computerinterface 209, with the computer 210 having in its inside a packetexchange 211 identical to the above packet exchange 201. Other elementsof structure are identical to those shown in FIG. 2(a). According to thestructure of FIG. 2(a), the extension control 205 first receives datasupplied from one of a plurality of pieces of terminal equipmentelectrically connected to the extensions 105. Then, the data thusreceived passes through the TDM path 202, after which it is delivered tothe packet exchange 201. Thereafter, the data is sent to a serverelectrically connected to one extension 105 through the transmissionpath opposite the above path. According to the structure of FIG. 2(b),data supplied from one of a plurality of pieces of terminal equipmentelectrically connected to the extensions 105 is first received by theextension control 205, and passes through the TDM path 202, followed bydelivering to the CPU 203. Then, the CPU ˜03 delivers the so-receivedserver use data to the computer interface 209 via the CPU bus 207. Afterthat, the computer interface 209 sends the data to the packet exchange211 of the computer 210 provided outwardly of the PBX 100. Further, thedata is supplied to the server electrically connected to one extension105 through the opposite route referred to above.

FIG. 3 shows the structure of the terminal equipment 101 connected tothe extension 105, for furnishing communication services of the PBXserver system according to the first embodiment of the presentinvention, to the user. The terminal equipment 101 basically comprisesan IC card control 301 for accepting a user entry in response to theinsertion of an IC card 30 therein, a main function 302 for providingfunctions identical to those of generally-used personal computers andwork stations, a server use control 303, a user entry control 304 and acommunication interface 305. In addition, the terminal equipment 101 iselectrically connected to a connector 308 of the extension 105 via anextension cable 307 similar to that employed in a normally-usedtelephone, after which it is connected via the connector 308 to theextension 105. When the terminal equipment 101 is electrically connectedto the extension 105 of the PBX 100, the communication interface 305communicates with the extension control 205 of the PBX 100, using thecontrol signal channel and the information signal channel of theextension 105. The server use control 303 is used to carry outcommunication control of data produced when the user makes use of theserver 104. The user entry control 304 is used to examine whether or notthe user entered in the terminal equipment 101 has been given a systemuse permit.

FIG. 4 shows, as an illustrative example, the structure of the server104 electrically connected to the extension 105, for furnishingcommunication services of the PBX server system according to the firstembodiment of the present invention to the user. The sever 104 comprisesan attached equipment interface 406 for providing interface, i.e., anelectrical interconnection between an attached equipment 407 controlledby the server 104 and a main function 402, an IC card control 401 forinitiating the entry of a server in the system in response to theinsertion of an IC card 408 therein, the main function 402 for providinga normal function (similar to that of a known server) serving as theserver, a server use control 403, a server entry control 404, and acommunication interface 405. In addition, the server 104 is electricallyconnected to a connector 308 of the extension 105 via an extension cable307 as a physical interface similar to that employed in a normally-usedtelephone, after which it is connected via the connector 308 to theextension 105. When the server is electrically connected to theextension 105 of the PBX 100, the communication interface 405communicates with the extension control 205 of the PBX 100, using thecontrol signal channel and the information signal channel of theextension 105. The server use control 403 is used to carry outcommunication control of data for using a server, which has beendelivered via the PBX 100 to the server 104 from the terminal equipment101 which has been used by the user. The server entry control 404 isused to examine whether or not the server entered in the PBX serversystem has already been registered in the system.

FIG. 5 shows another example of the terminal equipment 101 electricallyconnected to the PBX server system according to the first embodiment ofthe present invention. The terminal equipment shown in FIG. 5 differsfrom that illustrated in FIG. 3 in that the terminal equipment 101 isnot provided with the IC card interface and the IC card control 301.Thus, the terminal equipment according to the second embodiment of thepresent invention is activated to accept the entry of a user in thesystem when the user employs keys to thereby input a user ID and a userpassword. Other components, i.e., a main function 501, a server usecontrol 502, a user entry control 503, a communication interface 504have the same functions as those of the components shown in FIG. 3,respectively.

FIG. 6 illustrates another example of the server 104 for providing thecommunication service of the PBX server system according to the firstembodiment of the present invention. The present server is differentfrom the server shown in FIG. 4 in that the present server 104 is notprovided with the IC card interface and the IC card control 401. Thus,such a server initiates a process for the connection of the server tothe system when an operator who makes a request to connect the server tothe system, is keyed to thereby input a server ID and information aboutthe classification and attribute of the server. Other components, i.e.,a main function 601, a server use control 602, a user entry control 603,a communication interface 604 and an attached equipment interface 605have the same functions as those of the components shown in FIG. 4,respectively.

FIG. 7 shows the structure of the inside of the packet exchange 201 (or211). The packet exchange 201 comprises a packet control 701 used tocarry out the data transfer based on a packet exchange between each ofthe terminal equipment 101 and the server 104 both connected to theextension 105 of the PBX 100 and the PBX 100, and a terminal control 702used to manage or control the state of each terminal handled by a userallowed to utilize the PBX server system according to the firstembodiment of the present invention, and the state of the server 104entered so as to provide the communication service of the PBX serversystem being connected to each extension 105.

The packet control 701 includes an extension table 800 shown in FIG. 8,and manages or controls information about the terminal equipment 101 andits user connected for each extension of the PBX sever system andinformation about the server 104 connected for each extension thereof.The extension table 800 has an extension number 801 serving as an index,a terminal identification number 802, and a user ID 803. Further, whenattached equipment is of terminal equipment, the transfer of data in alogical multiplex mode can be realized upon transmission of data on orthrough a data link between the PBX and each terminal equipment with aview to using the server. Thus, the extension table 800 is used todistinguish between specific communications carried out between theterminal equipment 101 and the extension control 206. In addition, theextension table 800 also includes a logical channel number 804 assignedto each server, and a destination 805 indicative of a called destinationof data transmitted using the logical channel number 804. When theserver is now connected to the extension, a server ID is entered in theuser ID 803, whereas a logical channel number corresponding the usermaking use of the server referred to above is registered in the logicalchannel number 804. In addition, the user ID is entered in thedestination 805. Thus, when it is desired to transmit data to a desiredserver the user wants to use, a logical channel number corresponding toeach server is assigned without specifying physical addresses (extensionnumber, terminal identification number) of the server. Even when data istransmitted from the server to terminal equipment the user is nowemploying, a logical channel number corresponding to a user name isassigned in the same manner as described above.

FIG. 9 shows a server table 900 employed in the packet control 701. Theserver table 900 includes a server 901 serving as an index, an extensionnumber 902 to which the server is connected, a terminal identificationnumber 903 in which physical address information is entered, a logicalchannel number 904 assigned each time a user makes use of a server, auser ID 905 corresponding to the logical channel number 904, and anextension number 906 to which each user of the user ID 905 is connected.The packet control 701 is activated to logically connect between theuser and the server by reference to a combination of the extension table800 and the server table 900. More specifically, a server name the userwants to employ is recognized based on the logical channel number 804assigned when the user transmits data to the PBX 100, and the servername thus recognized is used to retrieve the server table 900, therebydetermining an extension number 902 and a terminal identification number903 corresponding to the server. As a result, a physical address fortransmitting data can be obtained. Then, a logical channel number 904corresponding to a user as a data transmit origin is assigned, followedby transmitting data to the PBX. When data to be transmitted from theserver to the user is received, an extension number 906 of the user ofdestination is retrieved from the server table 900, and the retrievedextension number is used to retrieve the extension table, therebydetermining a terminal identification number 802. At this time, at leastone of logical channels for data links between the PBX 100 and eitherthe terminal equipment 101 or the server 104 has been reserved for thetransmission of control information between the packet control 701 andeither the terminal equipment 101 or the server 104. According to theexamples illustrated in FIGS. 8 and 9, a logical channel number “256” isused to cause the control information to be transferred between thepacket control 701 and the terminal equipment 101. In addition, alogical channel number “512” is used to cause the control information tobe conveyed between the packet control 701 and the server 104. When thePBX 100 supports known packet exchange communication functions asprovided in the advice X.25 of CCITT, a logical channel number employedin known data communication based on a packet switching or exchangemode, and a logical channel number used in data communication intendedfor the use of the PBX server system, are separately established in thePBX 100.

FIG. 10 shows an entry table 1000 for the PBX server system, which isincluded in the terminal control 702. There has been entered in theentry table 1000, information about the user, which is input from thecontrol terminal 208 of the PBX 100 by the controller of the PBX serversystem. More specifically, the entry table 1000 includes user'sintrinsic information such as a user ID 1001 of a user who can use thePBX server system, a user name 1002, a password 1003 and an access class1004, etc. and information such as an extension number 1005 and anterminal identification number 1006, which varies with terminalequipment entered or registered by the user. In addition, the entrytable 1000 also stores a server ID of a server providing communicationservices, a server name, server's classification, server's attributeinformation, an extension number of the extension 105 to which theserver is connected, and a server's terminal identification number, allof which being inputted by the controller of the PBX server system. Theterminal control 702 checks using the entry table 1000 whether or not auser ID, a password and the like received when the user is entered inthe system and the user accepts a server available message, are correct.

FIG. 11 shows an LCN assignment table 1100 to be held in the server usecontrol 303 (or 502) of the terminal equipment 101. The LCN assignmenttable 1100 includes an LCN number 1101 assigned when data is transmittedto the server 104, classification 1102 of the server 104 as adestination to which data is transmitted using the LCN number, and anattribute 1103 of the server 104. The terminal control 702 checkswhether or not the user ID and the password fed from the terminalequipment 101 in which the user has made an entry, are correct. If theanswer is determined to be yes in the terminal equipment 702, then theinformation referred to above is delivered to the terminal equipment 101in which the user has entered. At this time, the information isregistered on the LCN assignment table 1100. When the user has finishedusing the terminal equipment 1101, the contents of information thusentered are deleted from the LCN assignment table 1100.

FIGS. 12 and 13 are flowcharts for describing the sequence of processescarried out by the terminal equipment 101, for detecting the entry of auser in the terminal equipment 101 of the PBX server system according tothe first embodiment of the present invention so as enable a server 104to be used from the terminal equipment 101 side.

FIG. 12 is a flowchart for describing the sequence of processes carriedout by the user entry control 304 of the terminal equipment 101 with theIC card control 301 upon entry of a user in the system. When the userinserts an IC card 306 for the system entry into the terminal equipment101 (Step 1200), the IC card control 301 detects the insertion of the ICcard 306 therein, and informs the user entry control 304 of the resultof its insertion. The user entry control 304 requires the IC cardcontrol 301 to read a user ID and a user's password from a given memorylocation of the IC card 306 (Step 1201). The user entry control 304receives therein the user ID and the password read from the IC card bythe IC card control 301 in response to the above request (Step 1202).Then, the user entry control 304 requires the communication interface305 to set up or establish a packet link for carrying out datacommunication in a packet exchange mode between the terminal equipment101 and the PBX 100 (Step 1203). Then, the user entry-control 304 waitsfor a packet-link setup message from the communication interface 305(Step 1204). At this time, if no response is given from the PBX evenwhen a predetermined period of time has passed after the communicationinterface 305 has been required to set up the packet link, or if apacket-link setup refusal or negative response is received from the PBX,then the communication interface 305 sends a user entry failure ornegative (NG) message to the user entry control 304. In addition, thecommunication interface 305 checks whether or not this message has beenreceived (Step 1205). When the user entry control 304 receives apacket-link setup message from the communication interface 305, the userID and the password read from the IC card in Step 1202 arecorrespondingly delivered to the communication interface 305 as data tobe firstly transmitted from the terminal equipment 101 to the PBX 100(Step 1206). Then, the user entry control 304 waits for either a userentry complete message or a user entry MG message, which is sent fromthe communication interface 305 (Step 1207). When the user entry control304 receives the user entry complete message for the use of the system,a use complete flag indicative of the state of the terminal beingutilized by the user is set to an OFF condition (Step 1208). The userentry complete message received from the communication interface 305includes a server ID of a server available to the user, a logicalchannel number used for data transmission, etc., and data entered in thelogical channel assignment table 1100. Now, the user entry control 304sends the data entered in the logical channel assignment table 1100 tothe server use control 303 (Step 1209). If necessary, a communicationprogram for employing a server which the PBX 100 has specified inresponse to the entry complete message is downloaded from the IC card306 (Step 1210). Then, the server use control 303 sends a datacommunication start message for the use of the server to thecommunication interface 305, thereby making it possible to use theserver from the terminal equipment 101 side (Step 1211) When the entryNG message is received from the communication interface 305 in Step1205, it is judged that a fault or malfunction has occurred in thesystem. Thus, the terminal equipment 101 is rendered incapable ofcarrying out data communication using a logical channel for the purposeof the use of the server. As a result, the user can use only theterminal equipment (Step 1212). When the user entry NG message isreceived from the communication interface 305 in Step 1207, an entryfailure message is sent to the user who has tried some system entries(Step 1213). Then, the number of the system entry failures isincremented (Step 1214). It is determined (in Step 1215) whether or notthe user ID employed by the user who has failed in the system entry hasalready been registered on an entry failure user ID list. If it isdetermined to be negative in Step 1215, then the user ID is newlyentered in the entry failure user ID list (Step 1216). Then, a timer Rhaving a period Tr is started (Step 1217). The timer R is activated forevery user IDs. If the entry of the identical user ID in the system doesnot fail after the period Tr has passed, then the user ID is deletedfrom the entry failure user ID list. If the user ID has already beenentered in the entry failure user ID list, then the timer Rcorresponding to the user ID is activated again (Step 1217). It is thendetermined (in Step 1218) whether or not the number of the entryfailures has reached a given M. If the answer is determined to be no,then the routine procedure terminates. If the answer is determined to beyes, then all the user IDs which have been registered on the entryfailure user ID list are entered in a user list requiring specialattention, i.e., a remark user list (Step 1219). Then, a timer K havinga period Tk is started (Step 1220). The timer K is used to measure orcount a period during which the user ID5 are stored in the remark userlist. When the timer K is timed out, a corresponding user ID is deletedfrom the remark user list. After the starting of the timer K has beenmade, the user IDs which have been registered on the remark user list,are sent to the PBX 100 (Step 1221).

FIG. 13 is a flowchart for describing the sequence of a user entryprocess carried out by the terminal equipment 101 free of the IC cardcontrol shown in FIG. 5 or the sequence of a user entry process carriedout by the user entry control (304 or 503) of the terminal equipmenthaving the IC card control when the user is re-entered in the PBX serversystem without drawing the IC card after the use of the server by theuser is temporarily stopped. In order to enter the user in the system,the user first depresses a keyboard. Then, when a user system entryrequest is detected (Step 1300), it is determined (in Step 1301) whetheror not a terminal in which the user has made an entry is an IC cardsystem, thereby distinguishing the above process. When it is determinedto be positive, the user is required to input a user name which has beenentered in the system in order to judge whether the re-entry of the sameuser in the system is made (Step 1302). When the user name is receivedfrom the main function 302 (Step 1303), the user name thus received iscompared with the user name registered on the IC card (Step 1304). If itis judged that they coincide with each other, then the user sends aserver use resumption message to the PBX 100 from the terminal equipment101 (Step 1305), thus finishing its routine procedure. If it is judgedthat they do not coincide with each other, then the user who has madehis entry procedure receives an entry NG message as being an improperuser (Step 1306), thereby terminating its routine procedure. If theanswer is determined to be no in Step 1301, then the user who desires anentry procedure is required to input his own user ID and password- (Step1307). The -user ID and password are received from the user as aresponse relative to its input request (Step 1308). It is checked (inStep 1309) at this time whether or not the received user ID has beenregistered on the remark user list which has stored the user ID of theuser has falsely been entered in the system (Step 1309). If the answeris determined to be yes, an entry NG message is sent to the user (Step1306), and its routine procedure terminates. If the answer is determinedto be no, the user entry control 503 requires the communicationinterface 504 to set up a data link for carrying out data communicationbased on a packet exchange mode between the terminal equipment and thePBX (Step 1310). As a response relative to the data link setup request,a packet link setup message is received (Step 1311) or a user entrynegative message is received (1312). When the user entry NG message isreceived at this time, the user who made a server system entry requestis inhibited from using the server, thereby enabling the user to useonly the terminal equipment 101 (Step 1313). When the packet link setupmessage is received in Step 1311, the user entry control 503 sends auser ID and a user password inputted from the user to the communicationinterface 504 (Step 1314). It is then determined (in Step 1315) whetheror not the user has been entered in the PBX 100. If the answer isdetermined to be yes, and the user can employ the system, then a usecomplete flag is sent to an OFF condition (Step 1316). In addition, theuser entry control 503 sends information about, for example, a servername and a server ID that the user can employ, to the server use control502 (Step 1317). Then, a communication program corresponding to theserver informed of such information from an external storage device ofthe terminal equipment 101 or the PEX is downloaded (Step 1318). Afterthat, a server user start message is sent to the communication interface504, thereby enabling data to be transmitted to the server (Step 1319).If the user who has made an entry request, receives a message to theeffect that the user has not been registered in the PBX 100 from thecommunication interface 504 in Step 1315, the user who has tried asystem entry procedure is informed of an entry NG message (Step 1320).Then, the number of entry failures is incremented (Step 1321). It isthen determined (in Step 1322) whether or not a user ID of the user whofailed in its entry has already been entered in the entry failure userID list. If the answer is determined to be no, then the user ID isentered again in the entry failure user ID list (Step 1323). Then, atime P having a period Tr is started (Step 1324). The timer P isactivated for every user IDs. If the entry of the identical user ID inthe system does not fail after the period Tr has passed, then it isdeleted from the entry failure user ID list. If the user ID has alreadybeen entered in the entry failure user ID list, then the timer Pcorresponding to the user ID is activated again (Step 1324). It is thendetermined (in Step 1325) whether or not the number of the entryfailures has reached a given number of times M. If the answer isdetermined to be no, then the routine procedure ends. If the answer isdetermined to be yes, then all the user IDs which have been registeredon the entry failure user ID list are entered in a user list requiringspecial attention, i.e., a remark user list (Step 1326). Then, a timer Khaving a period Tk is started (Step 1327). The timer K is used tomeasure or count a period during which the user IDs are held or storedin the remark user list. When the timer K is timed out, a correspondinguser ID is deleted from the remark user list. After the starting of thetimer K has been made, the user IDs which have been registered on theremark user list, are sent to the VBX 100 (Step 1328). Even if a processfor checking the user entry failure is realized by the packet control inthe PBX, the same functions as those described above can be achieved.

FIG. 14 is a flowchart for describing the sequence of processes, whichare carried out by the communication interface of the terminal equipment101, from the reception of a data link setup request message for thedata communication based on the packet exchange mode from the user entrycontrol to the response relative to its reception. When a packet linksetup request message is received from the user entry control (Step1400), the communication interface 305 sends the message to the PBX 100(Step 1401). At this time, a packet link setup wait timer T1 is started(Step 1402). It is then checked (in Step 1403) whether or not the timerT1 has been timed out. If the answer is of no, then it is determined (inStep 1404) whether or not the packet link setup confirm message has beenreceived from the PBX. When the packet link setup confirm message isreceived from the PBX before the timer T1 is timed out, the user entrycontrol is informed of a packet link setup message (Step 1405). Then, auser ID and a user password are received from the user entry control inresponse to the packet link setup message, thereby creating a data framein which the user ID and the password are assembled as user information.Then, the data frame is delivered to the PBX as user information of aconnection request packet used to specify a special destination addressfor the purpose of the use of the server system (Step 1406). Then, auser entry wait timer T2 in the PBX is started (Step 1407). It ischecked (in Step 1408) whether or not the timer T2 has been timed out.If the answer is of no, then it is (in Step 1409) determined whether ornot a response relative to user entry data has been received from thePBX. When data indicative of a user entry inquiry message is received asuser information of a call connected packet from the PBX before the timeT2 is timed out, the data indicative of the user entry inquiry messageis delivered to the user entry control (Step 1410). Incidentally, anentry complete message indicative of a user entry permit includes aserver ID of a server available to the user, a logical channel numberused for the data transmission, etc. If the timer T1 is timed out inStep 1403 or if the timer T2 is timed out in Step 1408, or if they aretimed out, then a user entry NG message is sent to the user entrycontrol (Step 1411), thus finishing its routine procedure.

FIGS. 15 and 16 are flowcharts for describing the sequence of processes,which are carried out by the server 104 in the PBX server systemaccording to the first embodiment of the present invention, from thedetection of a server entry to the state of the server being capable ofproviding communication services. A description will now be made of thesequence of the processes performed by the server with reference toFIGS. 15 and 16.

FIG. 15 shows the sequence of the processes carried out by a sever entrycontrol 404 of the server 104 upon entry of the server 104 having an ICcard control 401 in the system. When a server installer inserts an ICcard 408 for a system entry into the server (Step 1500), an IC cardcontrol 401 detects its insertion, and then informs a server entrycontrol 404 of the result of its insertion. The server entry control 404indicates a message showing the state of a server entry being underreception (Step 1501). The server entry control 404 requires the IC cardcontrol 401 to read server information such as a server name, a serverID, classification of a server which have been stored in given locationsof the IC card, from the IC card and to send the read resultthereto—(Step 1502). When the IC card control receives a request forreading the server information from the IC card, the IC card controlreads the server information from the IC card and then sends the readresult to the server entry control 404. Then, when the server entrycontrol 404 accepts the server information (Step 1503), the -serverentry control 404 requires a communication interface 405 to set up orestablish a data link for data communication based on a packet exchangemode, which data link being used to carry out data communication for theuse of the server between the server and the PBX (Step 1504). Then, theserver entry control 404 receives either a packet link setup confirmmessage or an entry NG message from the communication interface 405(Step 1506). If the packet link setup confirm message is received fromthe communication interface 405, then the server entry control 404requires the communication interface 405 to transmit the serverinformation to the PBX (Step 1507). Then, the communication interface405 waits for a response from the PBX relative to the transmission ofthe server information thereto (Step 1508). When the server entrycontrol 404 receives the entry complete message from the communicationinterface 405, it requires the communication interface 405 to enable thedata communication for the use of the server (Step 1509), followed bychanging the message on entry reception to a server available message(Step 1510), thereby terminating its process. If the entry NG message isreceived in Step 1506 or the entry NG message is accepted in Step 1508,then the server judges that it has failed in the system entry procedure,thereby disabling a system use. Accordingly, the server entry control404 changes the message on-entry-reception to a server unavailablemessage (Step 1511), thus finishing its routine procedure.

FIG. 16 is a flowchart for describing the sequence of system entryprocesses carried out by a server entry control 603 of a server free ofan IC card control such as that shown in FIG. 6. In order to -enter aserver in the system, a server installer first operates a keyboard.Then, when a server's system entry request is detected (Step 1600), theserver entry control 603 requires the server installer who has tried toconnect the server to the system to input server information such as aserver name, a server ID, classification of a server (Step 1601). Then,a user inputs the server information in response to its request. Whenthe server entry control 603 receives the server information (Step1602), it requires a communication interface 604 to set up a packet link(Step 1603). The subsequent steps are the same as the steps of 1505 to1511 carried out by the server entry control 404 of the server havingthe IC card control.

The operation of the inside of the PBX 100 employed in the PBX serversystem according to the first embodiment of the present invention willnow be described below.

FIG. 17 is a flowchart for describing the sequence of processes, whichare carried out by the packet control 701 in a packet exchange of thePBX 100, at the time that a packet for control data communication isreceived. When, for example, a connection request packet to the PBXserver system, a clear request packet, and a connection and/ordisconnection request packet for control data communication are sent tothe PBX from either the terminal equipment 101 in which a user made anentry or the server 104, the packet control 701 of the PBX 100 receivesthem (Step 1700). A special destination address is assigned to thepacket for the control data communication, which is used to employ theserver. It is then determined (in Step 1701) whether or not user data ofthe packet for the control data communication, which packet being usedto utilize a received server, is of data for calling for the entry ofeither the user or the server in the PBX server system. If the answer isdetermined to be yes, then it is determined (in Step 1702) whether ornot the data is used to enter either the user or the server in thesystem. If it is judged that the data is used to enter the user in thesystem, then a user ID and a user pass word is taken out from the dataso as to be sent to the terminal control 702, where their inquiryrequests are made (Step 1703). Then, a terminal identification number ofa terminal in which the user has entered, and a user ID are registeredon an extension table 800 of an extension number, to which the terminalequipment has been connected. The packet control 701 receives the resultof the inquiry of the user ID and the user password at the terminalcontrol 702 (Step 1704). When a user entry permit message is received, aserver name available to the user specified based on informationincluded in data indicative of a user entry permit message, and aspecific logical channel number used in the server on or through thedata link between the PBX and the terminal equipment, are entered incorresponding locations of the extension table 800 (Step 1705). Then,the user ID 905 of the user, and the extension number 906 of theextension connected with the terminal in which the user has made anentry, are registered in associated locations corresponding to aserver's empty logical channel number 904 on the server table 900 overall the servers to which users can be connected (Step 1706). Inaddition, a logical channel number 804 assigned newly in accordance withthe use of a server by a user is entered in each server's location ofthe extension table 800 to which the server is connected, and a user IDof each user is registered in a destination 805 thereof (Step 1707).Then, data having, as elements, information serving as a user entrycomplete message, about a server ID, a logical channel number, etc. anda user available server are sent to the terminal equipment in which theuser has made an entry, as user information of a call connected packet(Step 1708), thus finishing its routine procedure. In step 1704, theterminal control 702 is activated to make an inquiry about the user IDand the user password. As a result, the terminal control 702 judges thatan entry request has been made by a user who has not been registered inadvance as a system available one. When a message indicative of arejection of the entry of the user in the system is received, theterminal identification number 802 and the user ID 803 which have beenentered in the extension table 800, are deleted (Step 1709). Then, themessage indicative of the rejection of the entry of the user in the PBXserver system is sent to the terminal equipment in which the user hasmade an entry, as the user information of the call connected packet(Step 1710), followed by releasing a packet call, thus terminating itsroutine procedure. If it is judged that the data is used to enter theserver 104 in the PBX server system, then a server name, a server ID anda server's attribute is taken out from the data so as to be delivered tothe terminal control 702, where their inquiry requests are made (Step1711). Then, a server's terminal identification number and a server IDare registered on the extension table 800 of an extension number, towhich the server has been connected. The terminal control 701 receivesthe result of the inquiry about the server name, the server ID and theserver's attribute (Step 1712). When a server entry permit message isreceived, an extension number 902 to which the server is connected, anda terminal identification number 903 are registered on the server table900 (Step 1713). Then, a server entry complete message is sent to theserver as the user information of the call connected packet (Step 1714),thus terminating its routine procedure. In step 1712, the terminalcontrol 702 is activated to make an inquiry about the server name, theserver ID and the server's attribute. As a result, the terminal control702 judges that an entry request has been made by a server who has notbeen registered in advance as a server for providing communicationservices. When a message indicative of a rejection of the connection ofthe server to the system is received, the terminal identification number802 and the server ID 803 which have been entered in the extension table800, are deleted (Step 1715). Then, the message indicative of therejection of the entry of the server in the PBX server system is sent tothe server (Step 1716), thus finishing its routine procedure. If theanswer is determined to be no in Step 1701, then the data is used tocomplete the connection of the terminal equipment used by the user tothe system or to resume its connection. It is therefore judged (in Step1717) whether the data is used for either the completion of itsconnection or resumption of its connection. If it is judged that thedata shows the completion of its connection, then the user ID 803 isdeleted from the extension table 800. In addition, the user ID 905 ofdestination and the extension number 906 of the user are deleted fromthe server table 900. Then, a desired logical channel number 904corresponding to the user ID 905 of destination is read, and a user ID805 corresponding to the same logical channel number 804 relative toeach server's element in an extension table 800 of an extension to whicha server has been connected, is deleted (Step 1718). Incidentally, thepacket for the control data communication, which is used to transmit thedata referred to above, is of a clear request packet. If it is judged inStep 1717 that the data shows the resumption of its connection, theneach element of the same terminal identification numbers 802 of theextension table 800 is retrieved, and each user ID of the user who hasresumed the connection to the system is registered in each element ofthe user ID 803, which corresponds to the result of its retrieval. Whenthe user is entered in the system, the entry of the respective contentsin the server table 900 and the entry of the contents in the elementscorresponding to the respective available servers of the extension table800 are carried out (Step 1719) in the same procedure as describedabove, thus terminating its routine procedure.

FIG. 18 is a flowchart for describing the sequence of inquiry processesabout the user and the server, which are carried out by the terminalcontrol 702 in the packet exchange of the PBX 100. More specifically, itis judged whether or not information received at the packet control 701,for entering the entry of either the user or the server in the systemcan be regarded as appropriate. The terminal control 702 has an entrytable 1000, and compares the information which has been registered onthe table with the received data.

When the terminal control 702 receives a data inquiry request for thesystem entry from the packet control 701 (Step 1800), it is determined(in Step 1801) whether data is used to make an inquiry about either theuser or the server. If it is determined to be user inquiry data, then itis judged (in Step 1802) whether or not a user ID sent from the user hasbeen entered in a user ID 1001 of the entry table 1000. If the user IDcoincident with the user ID received from the user has been registeredon the entry table 1000 (Step 1803), then a password received from theuser is compared with a password 1003 registered on the entry table 1000(Step 1804). If the answer is determined to be yes (Step 1805), thenconnected extension number and terminal identification number ofterminal equipment 101 used by the user who made an entry request areentered in respectively corresponding elements of an extension number1005 and a terminal identification number 1006 of the entry table 1000(Step 1806). Then, a registered access class 1004 of the user is readfrom the entry table 1000 (Step 1807). Now, the terminal control 702 hasrecognized in advance the corresponding relation between theclassification of the server and the attribute thereof available inaccordance with each access class, and retrieves a user's availableserver from the access class 1004 (Step 1808). Then, the terminalcontrol 702 sends the user available server's name and its attribute tothe packet control 701 (Step 1809). If one identical to the user IDreceived from the user has not been registered on the entry table 1000in Step 1803, and if the password from the user does not coincide withthe registered password in Step 1805, then the user who made a systementry request is regarded as being an improper user subjected to therejection of the system use, so that the terminal control 702 sends aconnection negative (NG) message to the packet control 701 (Step 1810).If it is judged to be the server inquiry data in Step 1801, thenretrieval is made as to whether or not the server ID identical to thatreceived upon server inquiry has been registered on the entry table 1000is (Step 1811). If the answer is determined to be yes (Step 1812), thena judgment is made as to whether or not the information about theserver's attribute coincides with the information registered on theentry table 1000 (Step 1813). If the answer is determined to be yes,then the terminal control 702 informs the packet control 701 of amessage indicative of permission for the entry of the server in thesystem (Step 1814). Then, an extension number and a terminalidentification numbers connected with a server are registered on thecorresponding extension number 1005 and terminal identification number1006 of the entry table 1000 (Step 1815). If the server ID identical tothat received from the server has not been registered on the entry table1000 in Step 1812, and if the information about the server's attributeis inconsistent with the information registered on the entry table 1000,then the server who made a system entry request is regarded as being animproper server. As a result, the terminal control 702 sends an entry NGmessage to the packet control 701 (Step 1816). Thus, the terminalcontrol 702 informs the packet control 701 of the message—indicative ofeither the permit or rejection of the entry of either the user or theserver in the PBX server system as the result of the inquiry about theinformation subjected to the inquiry request from the packet control701.

The entry of the server in the system and the entry of the user in thesystem are completed in accordance with the processes referred to above,thereby starting a server's use. FIG. 19 is a flowchart for describingthe sequence of processes carried out by the server use control 303 atthe time of the delivery of the server use data. First of all, theclassification of each server to be used is received from the mainfunction 302 of the terminal equipment 101. Then, a logical channelnumber 1101 is retrieved from the received classification of each serverby reference to an LCN assignment table 1100 (Step 1902). The server usecontrol 303 sends the retrieved logical channel number to thecommunication interface 305 (Step 1903). Then, the server use control303 requires the main function 302 to output server use data therefrom(Step 1904). Thereafter, the server use data received at the server usecontrol 303 is transferred to the communication interface 305. On theother hand, a packet with a header added with the sent logical channelnumber is created as shown in FIG. 33(b), after which the communicationinterface 305 sends the server use data to a PBX 2800 in the form of thepacket.

A description will now be made of processes, which are carried out bythe packet control 701, from the reception of data for a server's usewith the PBX from terminal equipment employed by a user who has beenentered in the PBX server system to the delivery of the received data toa corresponding server with reference to FIGS. 20, 21 and 22.

FIG. 20 is a flowchart for describing the sequence of processes, whichare carried out by the packet control 701, from the reception of theserver use data to the entry of data in a server queue provided for eachserver. When the packet control 701 first receives the server use datafrom the user (Step 2000), it identifies a server to which the user madea use request (Step 2001). This identification can be determined byexamining a logical channel number on a data link between the terminalequipment 101 in which the user has made an entry and the PBX, whichnumber being used when the user transmits the server use data to the VBX100.

Then, data to be sent to the server are entered in a server queue 2100(see FIG. 21) provided for each server. At this time, it is checked (inStep 2002) whether or not data from the user identical to the registereduser has already been entered in the server queue 2100. This checkingprocess is based on the following purpose. Namely, when the informationis sent to the server 104 from the PBX 100, a server's process iscarried out in a most-efficiently processible data size, thereby makingit possible to carry out a data combination and a data separationbetween continuous two data. When the data from the identical user hasbeen entered in the server queue 2100, a comparison is made between thesize of the data received from the identical user, which is placed inthe rearmost location of the server queue 2100 assigned by the user andthe size of the data capable of most efficiently carrying out theserver's process (Step 2003). According to the server queue shown inFIG. 21, when data is sent from a user of a user ID as 0044 to a servern in an illustrated state, a comparison is made between the size of data2104 entered as a second data as viewed in a server queue 2100-n and thesize of the data capable of most efficiently performing the server'sprocess. If the size of the rearmost data in the server queue is smallerthan that of the most-efficiently processible data referred to above,then a comparison is made between the size of data obtained by addingthe rearmost data in the server queue and the data received from theuser and the size of the data capable of most efficiently carrying outthe server's process (Step 2004). If the size of the thus added data islarger than that of the latter, then the data thus added is divided intoa desired data size substantially equivalent to the size of the datacapable of most efficiently carrying out the server's process. Afterthat, each data thus divided is re-registered in the location at whichthe rearmost data of the server queue 2100 has been entered (Step 2005).Then, each data of the desired data size substantially equivalent to thedata size of the data capable of most efficiently carrying out theserver's process is separated from the added data, and the remainingeach data is subsequently processed as new received data (Step 2006).Then, a comparison is made between the size of the received datareferred to above and the size of the data capable of most efficientlycarrying out the server's process (Step 200). If the size of thereceived data is larger than that referred to above in Step 2007, thenthe received data is divided into the size of the data capable of mostefficiently carrying out the server's process, after which each data isentered in the server queue in data order (Step 2008). If it is judgedin Step 2002 that the data from the identical user has not beenregistered in the server queue, and if the size of the data capable ofmost efficiently performing the server' process is larger than that ofthe received data referred to above in Step 2003, then the same processas described above is carried out. If the size of the data capable ofmost efficiently performing the server's process is larger than that ofthe received data in Step 2007, then the received data from the user isentered in the last location of a server queue to which the user made ause request (Step 2009). If the size of the data capable of mostefficiently performing the server's process is larger than that of theadded data in Step 2004, then the received data is added to data, whichhas been entered in the rearmost location, of the data from theidentical user which has been entered in the server queue 2100, therebysetting up the thus processed data as new data which is to be entered inthe rearmost location. According to the server queue shown in FIG. 21,when the user of the user ID as 0044 sends data for using the server nto the VBX 100 so as to be received thereat, if the size of dataobtained by adding the received data to the rearmost data 2104 of thedata sent from the user of the user ID as 0044 which has been registeredin a server queue 2100-n is smaller than the size of the data capable ofmost efficiently carrying out the server's process, data obtained bycombining the received data and the data 2104 of the server queue 2100-nis reentered in the location at which the data 2104 is disposed.

FIG. 22 is a flowchart for describing the sequence of processes, whichare carried out by the packet control 701, for delivering data enteredin a server queue to a server. When a server's process is started (Step2200), a judgment is made as to whether or not data has been entered inthe server queue 2000 (Step 2201). If the answer is of yes, the packetcontrol 701 retrieves the server table 900 by reference to a servername, thereby determining an extension number required to transmit thedata to the server and physical addresses of the server such as aterminal identification number, etc. (Step 2202). Then, the server table900 is retrieved by reference to the user ID 905 so as to determine alogical channel number necessary upon delivery of data onto a data linkbetween the server and the PBX (Step 2203). Thereafter, the physicaladdresses and the logical channel number information are added as aheader to a data packet taken out from the server queue, after which theso-processed information is sent to an extension to which an intendedserver has been connected (Step 2204) Then, the routine procedurereturns to a process for examining whether or not the data has furtherbeen entered in the same server queue. If it is judged that the data isno longer entered in the server queue, then the next server queueretrieval is initiated. When the retrieval of all the server queues ismade (Step 2205), the routine procedure ends.

A description will now be made of processes for the separation of theuser from the PBX server system and for the completion of the use of theuser with respect -to the system with reference to FIGS. 23, 24 and 25.

FIG. 23 is a flowchart for describing the sequence of processes carriedout by the packet control when faults or malfunctions occur in the datalink between the server and the PBX or between the terminal equipmentand the PBX. When the terminal equipment in which either the server orthe user has made an entry is separated from the extension 105 in astate in which the data link is being set up between either the serveror the terminal equipment and the PBX, the packet control 701 detectsthat the malfunctions have occurred in the data link between either theserver or the terminal equipment and the PBX (Step 2300). It is thenchecked (in Step 2301) whether such malfunctions have been developed inthe data link-between the server and the PBX or between the terminalequipment and the PBX. If it is judged that the malfunctions have beendeveloped in the data link between the server and the PBX, then a serverunavailable message is sent to the terminal equipment in which the userentered in the server table 900 of the server has made an entry (Step2302). After the unavailable message has been sent to all the users ofthe server, corresponding servers of the server table 900 are cleared(Step 2303). Then, all the data entered in the server queue of theserver which has been subjected to the malfunctions referred to above,are released (Step 2304). Thereafter, the packet control 701 informs theterminal control 702 of a server name deleted from the server table 900(Step 2305), and structural elements corresponding to the server whichcaused the malfunctions to occur in the data link are deleted from theextension table 800 (Step 2306). When the malfunctions which haveoccurred in the data link are ascribed to the terminal equipment inwhich the user has made an entry, a user available server's name isretrieved from a corresponding portion of the extension table 800. Then,respective items corresponding to the user Jn the server table 900 ofthe retrieved server's name are deleted (Step 2307). Then, the packetcontrol 701 sends to the terminal control 702, the user ID of the userwhich has made an entry into the terminal equipment which caused themalfunctions to occur in the data link between the PBX and the terminalequipment (Step 2308), thereby deleting structural elementscorresponding to the terminal equipment from the extension table (Step2306).

FIGS. 24 and 25 are flowcharts for describing the sequence of processesfor completing the entry of the user in the terminal equipment. FIG. 24is a flowchart for describing the sequence of processes for completingthe entry of the user in the terminal equipment free of the IC cardcontrol, shown in FIG. 5 by way of example, which is employed in thesystem of the present invention, and the sequence of processes fortemporarily discontinuing the use of the PBX server system by the userat the terminal equipment having the IC card control, which is employedin the system of the present invention as shown in FIG. 3 by way ofexample. A message indicative of a request for the completion of theentry of the user in the PBX server system is first received in responseto the operation of the terminal equipment by the user (Step 2400). Whenthe message is received, data for informing the PBX of a messageindicative of the completion of the use of the PBX server system by theuser is created, followed by delivery of the same to the PBX (Step2401). Then, a use complete flag indicative of the fact that the userdoes not use the PBX server system is set to an ON condition (Step2402). It is thereafter judged (in Step 2403) whether or not theterminal equipment includes the IC card control. If the answer isdetermined to be yes, then the routine procedure ends. If the answer isdetermined to be no, then the user entry control requires thecommunication interface 504 to release the data link for carrying outthe data communication based on the packet exchange mode between theterminal equipment and the PBX provided that the entry of the user inthe PBX server system is terminated. (Step 2404). Correspondingly, thecommunication interface 504 sends a call control packet for making apacket link release request to the PBX. After the packet link releasehas been made, an LCN assignment table 1100 is deleted (Step 2405) andcommunication programs for the use of the Server are all erased (Step2406).

FIG. 25 is a flowchart for describing the sequence of processes forcompleting the entry of the user in the PBX server system at theterminal equipment with the IC-card control, shown in FIG. 3 by way ofexample, which is employed in the system of the present invention. Firstof all, the IC card control 301 detects that the user has drawn the ICcard 306, and informs the user entry control 304 of the result of itsdetection (Step 2500). In doing so, the user entry control 304 examineswhether or not the use complete flag is an ON condition (Step 2501). Ifthe answer is determined to be no, then the user entry control 304 sendsa message indicative of the completion of the use of the PBX serversystem by the user to the PBX (Step 2502). Then, the user entry control304 waits for a use complete confirm message from the PBX (Step 2503).When the use complete confirm message is received from the PBX, the userentry control 304 requires the communication interface 305 to releasethe packet link between the terminal equipment and the PBX (Step 2504).Then, an LCN assignment table 1100 is deleted after the packet link hasbeen released (Step 2505), and the communication programs for the use ofthe server are all deleted (Step 2506).

A description will now be made of the sequence of processes for the useof the PBX server system through a public line with reference to each ofFIGS. 26, 27 and 28.

FIG. 26 is a flowchart for describing the sequence of processes executedby the packet control 701, for making a system use request to the PBX100 of the PBX server system through a public line 106. When a packetcall is first sent to the public line control 206 from external terminalequipment, and information indicative of an incoming message to bedelivered to the packet exchange 201 is inputted as additive informationof a connection request packet at the time of the reception of thepacket call, the incoming message is delivered to the packet control701. When the public line 106 is used as an ISDN line, server addressinformation and user data are employed as the additive information ofthe connection request packet. When the packet control 701 detects themessage sent thereto through the public line (Step 2600), the packetcontrol 701 fetches a user ID and a user password from the incomingadditive information (Step 2601), and then sends the fetched informationto the terminal control 702 (Step 2602). Then, the terminal control 702compares the user ID and the password with those registered. If it isjudged (in Step 2603) that the incoming message has been sent from auser permitted to provide access to the PBX server system, then theterminal control 702 sends a response to the incoming message to thepublic line control. 206 (Step 2604). Then, a public line number 2701, auser ID 2702, a logical channel number 2703 and a server'sclassification 2704 of the user allowed to be connected to a public linetable 2700, are registered on the public line table 2700 shown in FIG.27 (Step 2605). Then, a user ID 905 and a user's public line number areregistered on a server table 900 (Step 2606). In order to distinguishbetween the extension and the public line, an identifier (e.g., “T”)indicative of the public line number is applied to the head of thenumber. Then, a logical channel number 804 utilized by the userconnected via the public line to the PBX server system is entered in acorresponding element of an extension table 800 (Step 2607). A logicalchannel number for the use of the server and a server's name andattribute corresponding to the logical channel number are sent to theterminal equipment which has been utilized by the user, which isconnected via the public line to the system (Step 2608). If the user isnot allowed to gain access to the PBX server system from the result ofthe comparison between the data referred to above and those registeredin Step 2603, the terminal control 702 sends a rejection response to theincoming message to the public line control 206 (Step 2609).

FIG. 28 is a flowchart for describing the sequence of processes forcompleting the use of the PBX server system by the user who has employedthe PBX server system through the public line 106 and for finishinguser's data communication. When a communication complete message of theuser is who has utilized the PBX server system through the public line,is received from the public line control 206 (Step 2800), a user ID 2702subjected to user's communication completion is taken out from thepublic line table 2700 (Step 2801). Then, a user ID 905 and a user'spublic line number 906 corresponding to the user ID 905 are deleted froma server table 900 of a server that the user could utilize, and aportion which is equivalent to each corresponding server's element on anextension table 800 and which corresponds to a user ID is deleted (Step2802). After a user use complete message has been sent to the terminalcontrol 702 (Step 2803), corresponding elements on the public line table2700 are deleted (Step 2804).

As described above, the present embodiment can bring about the followingadvantageous effects. A server using an extension of a PBX can beutilized, and terminal equipment and a server can be used in such amanner that they can freely travel over a PBX server system. Since aplurality of pieces of terminal equipment can simultaneously use thesame server, they are not placed on a waiting queue when server's userequests compete with each other, with the result that the server canreliably be used. According to another effect of the present embodimentas well, a server's name is designated without specifying a physicaladdress of a server, followed by sending data from a user. Therefore,the user can be connected to a desired server without taking intoconsideration a location at which the server is connected. According toa further effect of the present invention, a server use permit messageis given only to a user which has been entered in advance, therebymaking it possible to prevent an improper user from entering into thesystem. According to a still further effect of the present invention, itis possible to detect that the entry of the improper user in the systemhas been made through a predetermined number of times or more by thesame terminal equipment, thereby making it possible to separate theterminal equipment from the system. Therefore, a user who attempts toenter into the system cannot successively use the same terminalequipment. According to a still further effect of the present invention,an information access class of a user is registered in advance, and ˜user available server is sent correspondingly. In addition, acommunication means between the user and a user unavailable server isnot completely placed in use. It is therefore possible to connect eachserver having a variety of security levels to a server system.

A description will now be made of a PBX server system according to asecond embodiment of the present invention with reference to theaccompanying drawings.

FIG. 29 shows a PBX server system according to the second embodiment ofthe present invention. The PBX server system comprises a PBX 2900, aserver 2901 connected directly to the PBX 2900, telephones 102electrically connected to extensions 105, and a plurality of pieces ofterminal equipment 101. The present PBX server system differs from thePBX server system shown in FIG. 1 in that the server 2901 is directlyconnected to the PBX 2900.

FIG. 30 is a diagram schematically showing the structure of the insideof the PBX 2900. FIG. 30(a) shows the structure of the PBX in which apacket exchange 3001 for exchanging packet data between terminalequipment and each server is directly connected to a time-divisionmultiplex (TDM) path 3202 in the PBX 2900. Also connected to the TDMpath 3202 are a CPU 3003 for controlling the entire operation of the PBX2900, an extension control 3005 for controlling the electricalconnections among extensions 105, and a public line control 3006 forcontrolling the electrical connections among public lines 106. A memory3004 and a server interface 3009 for controlling the electricalconnection between control terminal equipment 3008 and the server 2901are electrically connected to the CPU 3003. The server interface 3009also controls the transmission of data through a server connection cable3010. FIG. 30(b) illustrates the structure of another PBX in which acomputer 3012 is electrically connected to a CPU 3003 of a PBX 2900through a computer interface 3011 with the computer 3012 having in itsinside a packet exchange 3013. Other elements of structure are identicalto those shown in FIG. 30(a). According to the structure of FIG. 30(a),the extension control 3005 first receives packet data supplied from oneof a plurality of pieces of terminal equipment electrically connected tothe extensions 105. Then, the packet data thus received passes throughthe TDM path 3002, after which it is delivered to the packet exchange3001. Thereafter, the packet data passes through the TDM path 3002again, and is sent via the CPU 3003 and the CPU bus 3007 to the serverinterface 3009 as serve use data. Then, the server interface 3009delivers the packet data to the server 2901 through the serverconnection cable 3010. According to the structure of FIG. 30(b), packetdata supplied from one of a plurality of pieces of terminal equipmentelectrically connected to the extensions 105 is first received by theextension control 3005, and then passes through the TDN path 3002,followed by delivering to the CPU 3003. The CPU 3003 then delivers thereceived server use data to the computer is interface 3011 via the CPUbus 3007. After that, the computer interface 3011 sends the packet datato the packet exchange 3013 of the computer 3012 provided outwardly ofthe PBX 2900. Further, the server use data is supplied from the packetexchange 3013 to the computer interface 3011, which, in turn, sends theserver user data to the server interface 3009 electrically connected tothe CPU bus 3007 identical to that previously used. Then, the serverinterface 3009 transmits the data to the server 2901 through the serverconnection cable 3010. The server 2901 shown in FIG. 30 differs from theserver illustrated in FIG. 4 and in that a communication interface ofthe server 2901 is electrically connected to the server connection cableunlike the communication interface of the server shown in FIGS. 4 and 6.Other elements of structure and functions are identical to those in thefirst embodiment.

FIG. 31 shows an extension table 3100 managed by a packet control 701 ofthe PBX 2900 employed in the second embodiment of the present invention.The extension table 3100 includes a terminal identification number 3102,a user ID 3103, a logical channel number 3104 and a server 3105 as adestination for each extension 3101 in the same manner as the extensiontable 800 shown in FIG. 8. However, each server is not registered on theextension table 3100.

FIG. 32 illustrates a server table 3200 controlled by a packet control701 of another PBX 2900 employed in the second embodiment of the presentinvention. The server table 3200 differs from the server table 900 shownin FIG. 9 in that elements descriptive of the extension number of theserver are unnecessary because the server 2901 is directly connected tothe CPU bus 3007, and a server name 3201 and a server's address 3202 onthe CPU bus represents information annexed to the server. In addition,the server table 3200 includes a logical channel number 3203, a user IDof destination 3204 and a user's extension number 3205 which areemployed as information about the user who makes use of a server. Bymaking use of these tables, servers can be utilized from terminalequipment connected to extensions respectively, even in the case of thePBX server system according to the second embodiment.

According to the second embodiment, data is sent to a server directlyconnected to a PBX. It is therefore possible to carry out datatransmission between the PBX and the server at a high speed and toimprove the response to a user.

Even in the case of the first and second embodiments, request messagesand data for the entry of a user and a sever in the system have beentransmitted using user data regions of packets for control datacommunication, such as a connection request packet, a call connectedpacket. However, they can also be transmitted using a data packet aftera packet link has been set up.

Having now fully described the invention, it will be apparent to thoseskilled in the art that many changes and modifications can be madewithout departing from the spirit or scope of the invention as set forthherein.

1. A method of user registration employed by a packet exchanger providedwith an exchanger unit connected with a plurality of data processingdevices and server devices through a communications line andtransmitting, upon receipt of a data packet from any of the dataprocessing devices, the data packet to a destination data processingdevice comprising the steps of: receiving a first data packet includingfirst user ID information from a first data processing device over thecommunications line; transmitting the received first user ID informationto a user ID checking unit making a check to determine whether the userID information is correct; registering terminal ID information of saidfirst data processing device; and registering, based on data ofpermission received from said user ID checking unit, said first user IDinformation and first logical channel information, which is designatedwhen data is transmitted to a first server device, in association withsaid terminal ID information.
 2. A method of user registration employedby a packet exchanger provided with an exchanger unit connected with aplurality of data processing devices and server devices through acommunications line and transmitting, upon receipt of a data packet fromany of the data processing devices, the data packet to a destinationdata processing device comprising the steps of: receiving a first datapacket including first user ID information from a first data processingdevice over the communications line; transmitting the received firstuser ID information to a user ID checking unit making a check todetermine whether the user ID information is correct; registeringterminal ID information of said first data processing device; andregistering, based on data of permission received from said user IDchecking unit, said first user ID information in association with saidterminal ID information and transmitting first logical channelinformation, which is designated when data is transmitted from saidfirst data processing device to a first server device, to said firstdata processing device over the communications line.
 3. A method of userregistration employed by a packet exchanger provided with an exchangerunit connected with a plurality of data processing devices and serverdevices through a communications line and transmitting, upon receipt ofa data packet from any of the data processing devices, the data packetto a destination data processing device comprising the steps of:receiving a first data packet including first user ID information from afirst data processing device over the communications line; transmittingthe received first user ID information to a user ID checking unit makinga check to determine whether the user ID information is correct;registering terminal ID information of said first data processing devicein association with a connection number to which said first dataprocessing device is connected; and registering, based on data ofpermission received from said user ID checking unit, first logicalchannel information, which is designated when data is transmitted to afirst server device, in association with said connection number.
 4. Amethod of user registration employed by a packet exchanger provided withan exchanger unit connected with a plurality of data processing devicesand server devices through a communications line and transmitting, uponreceipt of a data packet from any of the data processing devices, thedata packet to a destination data processing device comprising the stepsof: receiving a first data packet including first user ID informationfrom a first data processing device over the communications line;transmitting the received first user ID information to a user IDchecking unit making a check to determine whether the user IDinformation is correct; registering terminal ID information of saidfirst data processing device in association with a connection number towhich said first data processing device is connected; and transmitting,based on data of permission received from said user ID checking unit,first logical channel information, which is specified when data istransmitted from said first data processing device to a first serverdevice, to said first data processing device over the communicationsline.
 5. A method of user registration employed by a packet exchangerprovided with an exchanger unit connected with a plurality of dataprocessing devices and server devices through a communications line andtransmitting, upon receipt of a data packet from any of the dataprocessing devices, the data packet to a destination data processingdevice comprising the steps of: receiving a first data packet includingfirst user ID information from a first data processing device over thecommunications line; transmitting the received first user ID informationto a user ID checking unit making a check to determine whether the userID information is correct; registering terminal ID information of saidfirst data processing device in association with a connection number towhich said first data processing device is connected; and registering,based on data of permission received from said user ID checking unit,said first user ID information and first logical channel information,which is designated when data is transmitted to a first server device,in association with said connection number.
 6. A method of userregistration employed by a packet exchanger provided with an exchangerunit connected with a plurality of data processing devices and serverdevices through a communications line and transmitting, upon receipt ofa data packet from any of the data processing devices, the data packetto a destination data processing device comprising the steps of:receiving a first data packet including first user ID information from afirst data processing device over the communications line; transmittingthe received first user ID information to a user ID checking unit makinga check to determine whether the user ID information is correct;registering terminal ID information of said first data processing devicein association with a connection number to which said first dataprocessing device is connected; and registering, based on data ofpermission received from said user ID checking unit, said first user IDinformation in association with said connection number and transmittingfirst logical channel information, which is specified when data istransmitted from said first data processing device to a first serverdevice, to said first data processing device over the communicationsline.
 7. The method of user registration according to claim 6, whereinsaid first data packet includes a first password; and when thetransmission to said user ID checking unit is made, said first passwordis transmitted together with said first user ID information.
 8. A datapacket exchanger comprising: a line control unit connected with aplurality of data processing devices for each connection number througha communications line; a memory unit for storing information of the dataprocessing device for each of the connection numbers; and a packetcontrol unit, upon receipt by said line control unit of a first datapacket including first user ID information from a first data processingdevice over the communications line, transmitting the received firstuser ID information to a user ID checking unit making a check todetermine whether the user ID information is correct and, based on dataof permission received from said user ID checking unit, allowing saidmemory unit to store said first user ID information and terminal IDinformation of said first data processing device in association with aconnection number corresponding to said first data processing device. 9.The data packet exchanger according to claim 8, wherein said packetcontrol unit further allows said memory unit to store first logicalchannel information, which is designated when data is transmitted to afirst server device connected therewith through the communications line,in association with the connection number corresponding to said firstdata processing device.
 10. The data packet exchanger according to claim8, wherein said packet control unit further allows said line controlunit to transmit the first logical channel information, which isdesignated when data is transmitted from said first data processingdevice to a first server device, to said first data processing device.